1. Technical Field of the Invention
The invention relates to a cable harness production system comprising an electronic controller and at least one installation plate to which a plurality of mounting stations are fastened, each of said mounting stations supporting a receptacle for a functional element, which is directly connected to at least one cable of the cable harness, or is shaped as a cable installation aid, e.g. as a fork.
A cable harness is a length of cables that transmit signals for information or electrical power for energy supply. By the term “cable” here is meant, besides wires of copper, aluminium or other metals sheathed with insulating material, also coaxial cables, hollow waveguides and optical waveguide cables, such as glass-fibre cables or else steel twisted cables. The cables are held together by means of clips, cable straps, conduits or similar means and the finished cable harness connects together a plurality of functional elements such as plugs, connectors, switches or lights. The form of the cable harness is often to be adapted to specific spatial requirements on installation.
2. Description of the Prior Art
Numerous cable harnesses are used in automotive engineering, but also for electrical equipment, and those used, for example, in cars according to the state of the art can contain cables with a total length of several kilometers. Due to possible variants of the electrical equipment, a number of different cable harnesses is necessary even for vehicles that are otherwise the same or for the same devices.
The cables are assembled on a special workbench or on an installation board to form a cable harness, clamped together, wound or otherwise mechanically joined and electrically connected at their end points to the functional elements. In the prior art, the functional elements are retained in the receptacles of mounting stations and arranged on the installation plate and cable laying aids are arranged on the installation plate for guiding and angling the cables. In the simplest case, pins are used, which are partly hammered into the installation plate, in the prior art, however, column-like elements that support a fork or a guide angle as receptacle.
In the prior art, various functional elements exist, which are adapted to integration in a cable harness. Thus, e.g. U.S. Pat. No. 5,945,635, Coutaro Suzuki describes a special cable joiner that rests in receptacles on a columnar mounting station.
The reason for the elevated arrangement of the functional elements is that tools must in some cases act from a multiplicity of sides of the functional element and that the cable harnesses must be wound with textile tape or holding clips are to be stuck on the cable harness.
Other necessary processing steps include the threading of wires into conduits or the attachment of contacts to the lines, in particular the connecting of one contact to two lines and the fitting of conduits one inside the other. Each of these processing steps requires partly complex movement sequences, in which numerous possible errors open up. A further risk for production errors is the complexity of the overall structure of the cable harness.
Also to reduce these errors, it is an obvious step to automate the laying of cables and their connection to the functional elements, that is to say to have them performed, e.g., by robots.
European Patent EP 0300141 describes an industrial robot that fully automatically lays cables on an installation board and joins them. However, the disadvantage is the high investment for the robot, its connection to the installation plate and the continuous new programming for each individual cable harness and its variants. In particular for low production rates and individual parts of cable harnesses, it is therefore still economically appropriate to produce cable harnesses predominantly manually on installation boards with suitable auxiliary equipment.
The high complexity of most cable harnesses and the, in principle, higher defect quota for manual instead of automated work causes a comparatively high defect quota for cable harness production. Therefore, in the prior art, checking of the finished cable harness is unavoidable. The test set-up conventionally used at present are auxiliary cables arranged on the reverse side of the installation plate, by means of which a test instrument is connected to the ends of the cable harness just produced, as described inter alia in European Patent EP 0 300 141 and German Patent DE 939 341, Ulrich Kölm. A considerable disadvantage is that the laying of these auxiliary cables is very time consuming and, even with minor changes, work is often necessary not only in the vicinity of the auxiliary cables directly affected thereby, which after shifting of a portion become obstructions and therefore also have to be converted. The result of this is that in many cases the entire installation board has to be rebuilt.